Object of the present invention is a machine for orienting, straightening and aligning plastic vessels or bottles.
In particular, the present invention refers to those types of machines disclosed, for example, in Italian Patent n. 1,287,097 of the same Applicant, in which a hopper is provided in which bottles to be supplied are randomly and disorderly launched.
This hopper is substantially composed of a cylindrical wall rotating around a vertical axis.
On the external face of the cylindrical wall, a plurality of cradles are placed with below-placed dischargers that are substantially funnel-shaped, while on the internal face of the cylindrical rotating wall there are means for taking the bottles from the generally tapered bottom to the upper end of the cylindrical wall, where they fall into the above-mentioned cradles.
A carousel is provided in said machines, such carousel carrying a plurality of separators composing a plurality of vertical channels or openings in a number that is a multiple of the dischargers minus one.
The plurality of vertical channels or openings are arranged below the dischargers.
The below briefly described machines are currently equipped with means for changing the cradle and discharger sizes depending on the format change of vessels or bottles.
It has been found that, when the bottle format changes, current machines have not an optimum yield, since it is not possible to change the number of revolutions of the separators-carrying carousel with respect to the number of revolutions of the cylindrical rotating wall.
Another inconvenience is that, in currently known types of machines, it is not possible to change the phase between cylindrical rotating wall and separators-carrying carousel.
In fact, it has been found that, depending on bottle sizes, the bottle dropping times in dischargers change due to wears and bounces against discharger walls.
The dropping times that change depending on bottle shape and sizes result in spaces changing according to the speed of the dischargers-carrying cylindrical wall.
An optimum case would be the perfect phase between discharger and separator when the bottle arrives in the low discharger part and is about to enter the channel made of two nearby separators.
It has been attempted to solve the problem, for example in EP-A-1 209 103, by providing two independent motorizations or through electric or electronic adjustments.
It has been found that electric adjustments do not ensure the repeatability of phasing and speed changing operations and further the control system is difficult and with possible maintenance costs since it requires specialized workers.